It's been reported that the hard-man actor has done a spot of filming in the UK this week for the commercials, which apparently parody the iconic Rocky series.
Stallone is even due make an appearance to do a spot of baking at the bread factory in Wakefield, Yorkshire, and has apparently hired a stunt double who worked alongside him on The Expendables.
Sly is set to run up a flight of steps while holding a loaf of bread in each hand, The Sun reports.
A source told the paper: "The bosses at Warburtons have signed a real top-drawer name in Stallone. Sly doesn’t come cheap and he isn’t an obvious choice to promote bread — but he is bound to get people talking.
"They’re sure the investment will be worth it."
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